Saturday, 25 January 2020

The World's Oldest Meteorite Crater

The World's Oldest Meteorite Crater

My attention was drawn to this WEB PAGE (scroll down to the 21st January entry) as Nature wanted to use a photograph of mine to illustrate it. I, of course, said yes. 

We were at Barlangi Rock in January 2011 with a couple of geologist friends from University. In particular, John Bunting had been instrumental in bringing the site to the notice of the meteorite impact community and I was keen to see what he had found. You can see all my photos HERE

The first link is an introduction to THIS PAPER. This gives evidence that the impact has an age of 2229 ± 5 Ma. This is older than the Vredefort impact in South Africa and is the oldest impact found so far.

John's interest in the area was aroused by an observation made many years ago that shocked quartz had been seen in thin sections from the area. Also the (lack of) aeromagnetics of the area - see the figure below.

 The paper speculates that the area was covered by ice at the time of impact and the vaporisation of this may have influenced climate change. But in which direction the authors refuse to hazard a guess!

Barlangi (5 of 19)
On Barlangi Rock with the Meekatharra - Sandstone Highway on the right

No comments: